CASTLE RACE SERIES
SUNDAY 8 JUNE 2025
‘Superb triathlon to do. Beautiful scenery. Very well organised’.
Audrey M, 2024 Half Iron
Triathlon Château de Chantillly
‘Nothing to complain about, it was perfect! Beautiful setting, lovely course, well done to the teams!’
Loïc C, 2024 Olympic Triathlon Château de Chantilly
Dear participant,
Have you signed up or are you thinking of signing up for this huge challenge? This guide will provide you with all the information you need for the Bastion at the Château de Chantilly.
Known as ‘The Bastion’, this extraordinary triathlon will put the toughest athletes to the test. The Bastion features a 3.8km swim, a demanding 180km bike course and a magnificent 42.2km run through the grounds of the magnificent château.
A ‘bastion’ is a fort, a place where soldiers gather and prepare for the next battle. This resilience and will to fight will undoubtedly be needed to conquer this endurance race that will mark your life. This Full Iron distance race will test even the bravest warriors!
Our aim is to ensure that you have the best possible experience, that your loved ones have a great time cheering you on along the route, and celebrating with you in the events village. We want you to soak up the atmosphere, see the sights that make up Château de Chantilly, and the beautiful surrounding countryside that will be your playground for the day.
Please consult our 2025 Athlete's Guide when it becomes available. You'll find all the information you need for your welcome and arrival on site, including parking facilities, registration information, the events village and offers from our partners.
We wish you all the best with your training and pre-race preparations and look forward to seeing you at the start line for a race to remember.
Brian Adcock Race Director
PRE-RAC INFORM
1 CE MATION
SATURDAY 7 JUNE
The Bastion is one of the most memorable endurance races of your life.
REGISTRATION STORAGE AT NIGHT
Registration for all Bastion competitors will take place on Saturday 7 June. It is compulsory that competitors register and collect your race pack by the specified deadline
Your race pack will contain :
- 2 race numbers (with your name)
- 1 label sheet (with instructions)
- 1 participant wristband
- 1 spectator wristband
- 1 swim cap
- 3 transition bags
- 1 ankle timing chip
- 1 helmet label strip
SWIMMING TRAINING
There will be a practice swim on the Saturday for all Bastion competitors.
Check in on arrival, then head to the lake for a safety briefing by the Race Director.
Bikes are to be racked on Saturday afternoon and will be held there securely overnight.
SCHEDULES
These times for Saturday 7 June are approximate and will be confirmed as race day approaches.
Registration - 15:00 - 17:00
Bike racking - 15:00 - 17:00
Practice swim - 16:00
Race briefing - 17:00
BRIEFING OF COURSE
All competitors are required to attend the race briefing given by the race director.
This briefing will cover the important aspects of safety and the course that all participants should be aware of, and will give you the opportunity to ask any questions you may have.
The briefing will take place on Saturday 7 June at the Château. An invitation to all Bastion participants will be sent out prior to the race.
SUNDAY 8 JUNE
TRANSITION OPENING
The bike park will be open on race day from 05:30, and we suggest that competitors arrive at least an hour before the 07:00 start This could be a good opportunity to get reacquainted with the surroundings.
PLACEMENT AND TRANSITION
Please ensure that your bike, helmet and bags bear the appropriate stickers and numbers, and that you are wearing your wristband.
Athletes are responsible for ensuring that their bike and helmet are in good working order
TIMING
You will receive a timing device in your race pack when you register Make sure you wear it on your left ankle throughout the race.
HEALTH
There will be an experienced medical team and facilities in the event village, as well as mobile medical vehicles patrolling the course.
SUN CREAM
If it's a sunny day, we advise you to apply sun cream as soon as you get out of the water If you don't, you risk sunburn, which, as well as being painful, can lead to a rapid rise in your body temperature.
BAG FOR PERSONAL NEEDS
You will be able to obtain a personal feed bag at feed station 1 on the bike and run course. Please hand this bag, along with your nutritional requirements, to the registration team on the morning of race day.
Race morning. Supply bags will be stored in an orderly fashion at the designated area, but it will be your responsibility to locate your own bag and retrieve its contents. Aid station volunteers will not do this for you. Please note that we cannot guarantee that these bags will be returned to you. Please do not place valuables in these bags.
WITHDRAWAL
If you wish to withdraw from the event before or during the start of the race, please inform the information point and return your timing chip. It is important to inform us so that we can ensure that all competitors are accounted for on the day.
FINAL CHECKLIST
Photo ID
Bike water bottles
Race belt Puncture repair kit
Race licence
Spare inner tubes
Wetsuit Bike tools/pump
Goggles Socks
Towel Sun cream
Nutrition Hat/visor
Trisuit/race clothing
Trail running shoes
Bike Sunglasses
Cycle helmet Warm clothing
Cycle shoes Cash/card
YOUR RAC INFORMAT
2 CE TION
SWIM COURSE
The course consists of two laps of a 1.9 km loop. The start and finish will be at the Grand Canal entrance, in front of the Château. The Grand Canal is a 2.5km-long monumental work of art created by André Le Nôtre to rival Versailles, and surrounded by sumptuous formal gardens. Perfect for swimmers and their supporters!
CHECKLIST THE COURSE
The course consists of two laps of a 1.9km loop, for a total of 3.8km of swimming. The start and finish will be at the entrance to the Grand Canal, in front of the Château.
Race Director, Brian Adcock, will record an online briefing prior to race day, which will be shared on the event information page on our website This short online video will detail the course and safety instructions. If you are part of a relay team, please ensure that all members of your team have viewed it.
You will exit via the ramp in the centre of the Grand Canal. The cut-off time for swimming is 2 hours 20 minutes
Safety is at the heart of the event - we have safety boats and kayaks manned by fully trained safety representatives to look after your swim. If you feel you're in trouble, just lie on your back and raise your arm - someone will come and help you immediately Resting on the boat or kayak at any time during the race is acceptable with no implication on your race timings.
Swimmers will be manually and electronically counted into and out of the water for additional safety. Regular water quality and temperature tests are taken in the upcoming months, weeks and during the event. . This information will be posted on the Château de Chantilly competitor information page.
Timing chip
Goggles
Wetsuits - These will probably be compulsory, but the final decision will be taken at the race briefing
Floats or any other swimming aids are not permitted during the swim, but calf guards are permitted.
CYCLE COURSE
Your route consists of two laps starting from the Château. Cyclists will pass through some of the most beautiful tourist sites and towns in the Oise region.
All key junctions will be guarded by marshals, but remember that you will be riding on public roads that are not closed to traffic It is your responsibility to ride in accordance with the Highway Code, and FFTri referees will apply penalties to those who do not.
FEED STATIONS
There will be refreshments along the cycling route. We'll let you know in our pre-race communications what food will be available on the course.
BIKES
Don't forget that all athletes are recommended to use road or triathlon bikes. If you are an experienced cyclist, a TT bike is recommended.
NON-DRAFTING
This is a non-drafting race You will be expected to maintain a distance of at least 12m between your wheel and the back of the rear wheel of the rider in front of you. Should you wish to attempt to overtake you have 25 seconds to complete the manoeuvre.
RELAY TEAMS
Relay teams must ensure that the timing chip is passed between team members during the transition. This must be done next to the position of your bike on the bike rack.
WASTE
Competitors must not litter the course. If they are caught littering, they will be disqualified.
OTHER COMPETITORS
Please note that you will be sharing the cycling course with competitors of other distances. Please respect the signs and the marshals' instructions when you are on the course.
RESPECT FOR ALL
Respect other competitors, event staff and members of the public during the race.
CYCLE COURSE OVERVIEW
The route consists of 2 laps of a 90km course around the stunning Oise countryside. Passing through Forêt de Chantilly and Forêt d’Ernmenonville, before skirting the edge of Bois du Roi this beautiful route will truly put you through your paces.
THE ROUTE
Heading south from the château the route takes cyclists through the stunning Forêt de Chantilly and past the entrance to Parc Astérix Passing the beautiful man-made reservoir of Étang de Vallière and the quintessential town of Mortefontaine, cyclists will then head east through the villages of Montaby and Loisy After passing through the town of Ermenonville, cyclists continue east passing the Château d”Ermenonville and the famous JeanJacques Rousseau Park. After the towns of Montagny-Sainte-Félicité and Nanteuil-le-Haudouin, athletes then head north-west towards Versigny and Baron. The route then heads north-east to Rosière and then northwards to Le Luat Here, cyclists turn left and head east through Ducy, before then
heading north through Rully. Competitors head north-west again towards Néry before finally turning homewards through Raray and Brasseuse. Upon reaching Senlis and passing its famous Cathedral the route heads past Chantilly Polo Club before returning to Château de Chantilly The route will be on open public roads and not closed to traffic.
ELEVATION
The course has a total of 630m ascent per lap. The majority of the route is flat, with one steep climb in the first half of the loop.
RUN COURSE
On the run course, the athletes will pass through the magnificent grounds of the Château. This flat and fast run course is perfect for those looking to complete the run section in a quick time.
THE COURSE
Much of the race route is off-road and many competitors choose to wear trail shoes or multi terrain running shoes.
The finish line and event village are located near the castle and the Grand Canal, where there will be plenty of refreshments and drinks on offer.
THE COURSE REMAINS OPEN TO THE PUBLIC
Please take care when running on all sections of the route, as there may be walkers.
WASTE
Competitors must not litter the course If they are caught littering, they will be disqualified.
RESPECT FOR ALL
Respect other competitors, event staff and members of the public during the race.
RUN COURSE OVERVIEW
The run course takes athletes through the picturesque grounds of the Château, getting outside the Castle towards the famous Grandes Stables coming back inside the Gardens through l’Ile D’amour (The island of love). Triathletes will complete four 10.5 km loops, totaling 42 km.
THE ROUTE
The race takes place within the beautiful grounds of the Château de Chantilly estate, consisting of four laps of a 10 km course. Runners will begin in the Parc Hameau, passing scenic reservoirs and winding through the estate's charming gardens. Along the way, they will encounter iconic landmarks such as the Grille d'Honneur, the Grille de Jeu de Plume, and the Jardin Anglais. The route then loops around the Grand Canal and takes runners through parts of the formal gardens, past Maison de Sylvie, and into the Parc de Sylvie, including its labyrinth.
THE TERRAIN
This stunning, fast, and flat course features a mix of grass, tracks, and paths. Multi-terrain shoes are recommended for optimal performance.
ELEVATION
The course has a total of 51m ascent per lap. The route is largely flat, with a few gentle ascents and descents.
TIME LIMITS
The cut-off time for the Bastion race is 16 hours.
AFTER SWIMMING
2 hours 20 minutes (+10 minutes for transition)
VELO
9 hours and 45 minutes (allowing an average speed of 24km/h)
AT THE EXIT OF T2
10am (at the start of the run)
FULL LIMIT (MUST HAVE STARTED THE LAST LAP OF THE RUN )
14 hours and 30 minutes (from the start of the race).
If the competitor has not completed the third lap of the run before 21.30 they will not be allowed to continue and will be directed to the finish.
REFUELLING
The Castle Race Series will provide you with full refreshments and will tell you what food will be available on the course as the event approaches.
ON THE SWIMMING COURSE
There will be a floating pontoon on the swim course, which will be stocked with a selection of drinks
Drinks will be dispensed in cups. Please return used cups to the pontoon, where officials will ensure that they are disposed of responsibly.
ON THE BIKE
Each aid station will be preceded by a large container ready to collect your empty water bottles or rubbish. There will also be a container about 50 metres after the aid station. There will be refreshment posts at 25 km, 45 km and 70 km.
A team of volunteers will provide a selection of food and drink
Drinks at these stations will be distributed in bike-specific containers.
ON THE RUN COURSE
There will be at least two refreshment stations on each of the two laps.
A team of volunteers will provide a selection of food and drink.
Drinks at these stations will be distributed in cups. Please use the litter bins further along the course to dispose of your rubbish rather than throwing it in the castle grounds
During your race, you may be joined by competitors from shorter races who have started after you. Don't be put off by the fresh-legged runners who overtake you (they'll be wearing different coloured bibs)!
POST RA INFORMA
3
ACE ATION
AFTER THE RACE
After your race, you'll receive your medal at the finish line, right next to the recovery area where you can get something to eat.
HOT MEAL
A free hot meal will be available in the marquee where the race briefing took place. Please present your wristband.
T-SHIRT
Make sure you collect your Bastion tshirt from the Bastion marquee after the race.
PRIZES
BACK PACK
Your registration includes a unique ‘Bastion’ rucksack. You can collect it from the Bastion marquee after your race.
MEDALS, AGE GROUPS AND PRIZE-GIVING CEREMONY
The top 3 finishers will receive a trophy and a gift! There will also be age group trophies for the first places in the 40+, 50+ and 60+ categories, as well as prizes for all places.
All podium finishes will take place in the afternoon. More information will be given by the commentators during the day or at any time at the information tent
EACH COMPETITOR WILL RECEIVE
- A medal - A rucksack
- A Bastion technical t-shirt
- A well-deserved hot meal at the end of the race (you can claim it by entering the competitors' tent and presenting the wristband worn during the race).
- A free massage by one of our masseurs.
